Understanding the gas permeability of your packaging and materials is crucial for ensuring product integrity and shelf life. We know that selecting the right barrier material can prevent spoilage, preserve quality, and meet regulatory requirements. This test provides the objective data you need to make informed decisions about your material selection and packaging design. It is a fundamental step in quality control and product development for a wide range of industries.

Material Gas Barrier Measurement

The gas permeability test is a standardized laboratory procedure used to quantify how easily a gas, such as oxygen, carbon dioxide, or nitrogen, can pass through a solid material. This measurement is critical for evaluating the barrier properties of materials used in food packaging, pharmaceutical blister packs, and industrial applications. The test determines the Gas Transmission Rate (GTR), which indicates the volume of gas permeating through a unit area of the material over a specific time under set conditions of pressure and temperature. A lower GTR signifies a better barrier, which is essential for protecting sensitive products from degradation. The procedure is typically performed using specialized equipment known as a gas permeability tester, which creates a controlled environment to ensure accurate and repeatable results. This data is indispensable for manufacturers who need to guarantee their packaging will perform as expected throughout the product’s distribution and shelf life.

Gas Transmission Rate Analysis

Gas Transmission Rate (GTR) analysis provides the specific quantitative data resulting from a gas permeability test. It is expressed as the volume of gas that permeates through a unit area of the material per day under a specified pressure differential. This rate is the fundamental metric for comparing the barrier performance of different materials or different batches of the same material. Accurate GTR analysis helps in predicting the shelf life of packaged goods, optimizing packaging thickness, and ensuring compliance with industry standards. The analysis process involves precise control of temperature, humidity, and gas pressure on both sides of the test specimen. We at Labthink provide the instruments and methodologies required for this critical analysis. By understanding the GTR, manufacturers can make evidence-based decisions to improve their products’ quality and safety, ultimately reducing waste and enhancing consumer satisfaction.

Permeation Testing Method Details

Permeation testing involves detailed methodologies to measure gas flow through a material. The most common methods are the differential-pressure method (or manometric method) and the coulometric method (for oxygen transmission rate test). In the differential-pressure method, the test gas is introduced at a higher pressure on one side of the sample, and the pressure increase on the low-pressure side is measured to calculate the transmission rate. The coulometric method, often using a coulometric sensor, measures the oxygen molecules have permeated through the material and reached the sensor. The test sample is mounted as a sealed barrier separating two chambers, and the entire apparatus form a temperature-controlled environment to ensure consistency. The process requires meticulous preparation, including conditioning the sample and calibrating the instrument, to eliminate variables that could affect the result. This rigorous approach ensures that the obtained permeability is a reliable intrinsic property of the material being tested.

Conclusion

We manufacture a series of Gas Permeability Testers that measure the gas transmission rate of materials. Our instruments use methods such as the differential-pressure method and the coulometric sensor method. The testers are designed for various gases, including common, toxic, flammable, or explosive ones, and support ASTM testing standards. Specific models include the VAC-V1 (EX), VAC-V2 (EX), and the C206H Oxygen Transmission Rate Test System, which you can learn more about through our gas permeability analyzer resources.